LPIC-1 Practice Questions 1 — 50 Questions

Question 1

Which TWO commands can be used to display the current runlevel of a SysV init system?

Accepted Answer

who -r. The `who -r` command displays the current runlevel and the time it was last changed, making it a valid way to check the runlevel in a SysV init system. The `runlevel` command directly outputs the previous and current runlevel, which is the standard tool for this purpose.

Answer

init 3

Answer

telinit

Answer

systemctl get-default

Question 2

A system administrator notices that the system boots to the graphical interface but wants to change it to boot to a non-graphical multi-user target. Which command will make this change persistent?

Accepted Answer

systemctl set-default multi-user.target. `systemctl set-default multi-user.target` changes the default systemd target to `multi-user.target`, which boots to a non-graphical multi-user environment. This change is persistent across reboots, as it updates the symlink `/etc/systemd/system/default.target` to point to `multi-user.target`.

Answer

systemctl isolate multi-user.target

Answer

systemctl enable multi-user.target

Answer

systemctl start multi-user.target

Question 3

An administrator wants to change the ownership of a file to user 'jane' and group 'staff'. Which command should be used?

Accepted Answer

chown jane:staff file. The `chown` command with the syntax `chown user:group file` changes both the user and group ownership of a file in a single command. This is the standard POSIX syntax, where a colon separates the user and group names, allowing the administrator to set ownership to user 'jane' and group 'staff' atomically.

Answer

chown jane.staff file

Answer

chgrp jane staff file

Answer

chown jane staff file

Question 4

An administrator wants to add a kernel parameter 'quiet splash' to the default boot entry. Which file should be edited?

Accepted Answer

/etc/default/grub. The correct file to edit is /etc/default/grub because it is the main configuration file for GRUB 2 where kernel boot parameters like 'quiet splash' are defined in the GRUB_CMDLINE_LINUX_DEFAULT variable. After editing this file, the administrator must run update-grub (or grub-mkconfig) to regenerate the actual boot configuration file /boot/grub/grub.cfg.

Answer

/etc/grub.d/00_header

Answer

/etc/grub.conf

Answer

/boot/grub/grub.cfg

Question 5

Refer to the exhibit. The root filesystem is at 95% capacity. Which option will free space on the root filesystem?

Accepted Answer

Move /var/log to /mnt/backup and create a symlink. Moving the /var/log directory to a separate partition or filesystem (e.g., /mnt/backup) and creating a symbolic link from /var/log to the new location frees space on the root filesystem without losing log data. This approach preserves the filesystem hierarchy and allows logs to continue growing on a different volume, preventing the root filesystem from filling up.

Answer

Resize /dev/sda1 using resize2fs

Answer

Delete all files in /var/log

Answer

Move /home to /mnt/backup and create a symlink

Question 6

A system administrator notices that a server with an ext4 filesystem fails to boot after editing /etc/fstab. The error message indicates that the root filesystem cannot be mounted. Which of the following is the most likely cause?

Accepted Answer

The UUID or device name for the root filesystem is incorrect.. If the UUID or device name for the root filesystem in /etc/fstab is incorrect, the kernel cannot locate the root device during boot, resulting in a mount failure. The init process reads /etc/fstab to mount the root filesystem, and any mismatch—such as a typo in the UUID or a stale device path—will cause the system to drop into emergency mode.

Answer

The root filesystem is mounted read-only.

Answer

The swap partition entry is missing.

Answer

The filesystem type is specified as 'auto' instead of 'ext4'.

Question 7

Refer to the exhibit. On boot, which filesystem will be checked first by fsck?

Accepted Answer

The root filesystem (/). The root filesystem (/) is checked first by fsck because it is mounted read-only during the initial boot phase, and fsck must verify its integrity before the system can proceed to mount other filesystems. The order of filesystem checks is determined by the fs_passno field in /etc/fstab, where the root filesystem typically has a passno of 1, ensuring it is checked before any filesystem with a higher passno value.

Answer

The swap partition

Answer

The CD-ROM device

Answer

The /boot filesystem

Question 8

The system is unable to mount a filesystem that should be identified by UUID 1234-5678. The administrator checks /etc/fstab and finds the entry: UUID=1234-5678 /data ext4 defaults 0 2. What is the most likely cause of the mount failure?

Accepted Answer

The symlink for UUID 1234-5678 is broken.. The most likely cause is that the symbolic link for UUID 1234-5678 is broken. In Linux, UUID-based mounts in /etc/fstab rely on symlinks in /dev/disk/by-uuid/ that point to the actual block device. If the symlink is missing or points to a non-existent device (e.g., after a disk reorder or hardware change), the system cannot resolve the UUID to a device, causing the mount to fail even if the filesystem itself is intact.

Answer

The /data mount point does not exist.

Answer

The device /dev/sda1 is not formatted with ext4.

Answer

The UUID in the fstab entry is incorrect.

Question 9

Which TWO commands can be used to display information about the CPU(s) in a Linux system? (Choose two.)

Accepted Answer

cat /proc/cpuinfo. Options D and E are both correct. `cat /proc/cpuinfo` reads the virtual file /proc/cpuinfo which the kernel populates with detailed CPU information for each core, such as model name, cache size, and flags. `lscpu` is a utility that collects CPU information from /proc/cpuinfo and sysfs, presenting it in a human-readable tabular format. Both commands are standard on Linux for displaying CPU details.

Answer

uname -m

Answer

lsusb

Answer

cpufreq-info

Question 10

Arrange the steps to configure a static IP address on a Linux system using the command line.

Accepted Answer

Step 1: Open the network configuration file (e.g., /etc/network/interfaces).
Step 2: Configure the interface with static IP, netmask, gateway, and DNS.
Step 3: Save and exit the file.
Step 4: Restart the networking service.. Static IP configuration requires editing the appropriate config file, then restarting networking to apply changes.

Answer

Step 1: Restart the networking service.
Step 2: Open the network configuration file.
Step 3: Configure the interface with static IP, netmask, gateway, and DNS.
Step 4: Save and exit the file.

Answer

Step 1: Open the network configuration file.
Step 2: Save and exit the file.
Step 3: Configure the interface with static IP, netmask, gateway, and DNS.
Step 4: Restart the networking service.

Answer

Step 1: Configure the interface with static IP, netmask, gateway, and DNS.
Step 2: Restart the networking service.
Step 3: Open the network configuration file.
Step 4: Save and exit the file.

Question 11

Refer to the exhibit. What is the current default target?

Accepted Answer

multi-user.target. The current default target is multi-user.target because the output of the `systemctl get-default` command shows 'multi-user.target'. This target provides a non-graphical, multi-user console environment without a display manager, which is the standard default on many server-oriented Linux distributions.

Answer

emergency.target

Answer

rescue.target

Answer

graphical.target

Question 12

A system administrator needs to install the latest version of a package named 'webapp' from a third-party repository that has been added to the system. Which command should be used to update the package list and install the package in one step?

Accepted Answer

apt-get update && apt-get install webapp. It first runs `apt-get update` to refresh the local package index from all configured repositories (including the third-party one), then uses `&&` to conditionally execute `apt-get install webapp` only if the update succeeds. This ensures the latest version available from the third-party repository is fetched and installed in a single command sequence.

Answer

apt-get upgrade webapp

Answer

dpkg -i webapp.deb

Answer

apt-cache search webapp && apt-get install webapp

Question 13

A system administrator needs to locate the largest directories under /var to free up disk space. Which command is most appropriate?

Accepted Answer

du -sk /var/* | sort -rn. `du -sk /var/* | sort -rn` calculates the disk usage in kilobytes for each top-level item under /var, then sorts them numerically in reverse order, showing the largest directories first. This directly addresses the need to locate the largest directories to free up space, as `du` reports actual disk usage (including subdirectories) rather than file sizes.

Answer

df -h /var

Answer

find /var -size +100M

Answer

ls -lS /var

Question 14

Which TWO tools can be used to query DNS records? (Choose two.)

Accepted Answer

nslookup. A is correct because nslookup is a classic DNS query tool that sends DNS queries to name servers to resolve domain names to IP addresses or vice versa. It directly queries DNS records (A, AAAA, MX, CNAME, etc.) using the DNS protocol (UDP/TCP port 53).

Answer

ss

Answer

ping

Answer

traceroute

Question 15

The system administrator wants to add a new swap partition on /dev/sdb2. After creating the partition, which command should be used to initialize it as swap?

Accepted Answer

mkswap /dev/sdb2. The `mkswap` command is specifically designed to initialize a partition or file as a swap area by writing a swap signature (UUID and swap superblock) to the device. After creating the partition, you must run `mkswap /dev/sdb2` to set it up for use as swap before activating it with `swapon`.

Answer

mkfs.ext4 /dev/sdb2

Answer

fsck /dev/sdb2

Answer

swapon /dev/sdb2

Question 16

During system startup, GRUB 2 displays a prompt. Which command should be typed at the GRUB prompt to boot the currently selected entry normally?

Accepted Answer

boot. At the GRUB 2 prompt, the 'boot' command instructs GRUB to load the operating system using the currently configured kernel, initrd, and root device settings. This is the standard way to proceed with normal booting after any manual adjustments or when the menu is not displayed. Without 'boot', GRUB remains at the prompt and does not transfer control to the kernel.

Answer

normal

Answer

linux

Answer

initrd

Question 17

A user reports that a cron job is not executing. The cron job is defined in /etc/crontab. The administrator checks the system logs and finds no errors. Which command should the administrator use to verify that the cron daemon is running?

Accepted Answer

pgrep cron. `pgrep cron` searches the process table for processes named 'cron' and returns the PID(s) if running. This is a quick, reliable way to verify the cron daemon is active without parsing full process lists or relying on systemd-specific commands.

Answer

systemctl status cron

Answer

crontab -l

Answer

ps aux | grep cron

Question 18

Which sed command will replace the first occurrence of 'foo' with 'bar' on each line of a file?

Accepted Answer

sed 's/foo/bar/' file. The default behavior of the `s` (substitute) command in sed is to replace only the first occurrence of the pattern on each line. Without a numeric flag, `sed 's/foo/bar/' file` replaces the first 'foo' on each line with 'bar'. The `g` flag would replace all occurrences, not just the first.

Answer

sed 's/foo/bar/g' file

Answer

sed 's/foo/bar/0' file

Answer

sed 's/foo/bar/2' file

Question 19

Which two commands can be used to send a test email from the command line to verify SMTP functionality? (Choose two.)

Accepted Answer

mail -s test user@example.com. The `mail` command (option C) sends an email via the local MTA, directly testing SMTP delivery. The `sendmail` command (option D) with a piped message also invokes the MTA to deliver the email, verifying SMTP functionality. Both commands rely on the system's configured MTA to handle SMTP communication.

Answer

telnet localhost 25

Answer

mutt -s test user@example.com

Answer

sendmail -bv user@example.com

Question 20

A Linux administrator is managing a server that uses RPM-based package management. They need to find which installed package provides the '/etc/ssh/sshd_config' file. Which command should they use?

Accepted Answer

rpm -qf /etc/ssh/sshd_config. The correct command is `rpm -qf /etc/ssh/sshd_config`. The `-q` flag queries the RPM database, and `-f` (or `--file`) tells RPM to find which installed package owns the specified file. This is the standard way to map a file back to its originating package in RPM-based systems.

Answer

rpm -qi /etc/ssh/sshd_config

Answer

rpm -ql /etc/ssh/sshd_config

Answer

rpm -qa | grep sshd_config